@article{KleinDarvinMeinkeetal.2013,
  author    = {Klein, Julia and Darvin, Maxim E. and Meinke, Martina C. and Schweigert, Florian J. and M{\"u}ller, Kerstin E. and Lademann, J{\"u}rgen},
  title     = {Analyses of the correlation between dermal and blood carotenoids in female cattle by optical methods},
  series = {Journal of biomedical optics},
  volume    = {18},
  journal   = {Journal of biomedical optics},
  number    = {6},
  publisher = {SPIE},
  address   = {Bellingham},
  issn      = {1083-3668},
  doi       = {10.1117/1.JBO.18.6.061219},
  pages     = {6},
  year      = {2013},
  abstract  = {Herd health programs for the maintenance of welfare and productivity in cattle need efficient tools for monitoring the health of individual animals. Recent reports demonstrate that the oxidative status is related to various stress conditions in dairy cows. Biomarkers, among other carotenoids, could serve as indicators of stress originating from the environment (e.g., heat stress or sun radiation) or from the animal itself (e.g., disease). To date, only invasive in vitro tests are available to assess the oxidative status in cattle. The present study compares the results of optical noninvasive in vivo measurements of dermal carotenoids in cattle udder skin using an LED-based miniaturized spectroscopic system (MSS) with those obtained by photometric analysis of beta carotene in whole blood samples using a portable device. Correlations between the concentrations of dermal and blood carotenoids were calculated under consideration of the nutritional status of the animals. Significant correlation (R = 0.86) was found for cattle with a moderate to obese body condition. Thus, the blood and skin concentrations of the marker substance beta carotene are comparable under stable stress conditions of the cattle. This demonstrates that the MSS is suitable for noninvasive assessment of dermal carotenoid concentrations in cattle.},
  language  = {en}
}
@article{MuellerAltenkampRailaetal.2011,
  author    = {M{\"u}ller, Kerstin E. and Altenkamp, Rainer and Raila, Jens and Schmidt, Daniel and Dietrich, Robert and Hurtienne, Andrea and Wink, Michael and Krone, Oliver and Brunnberg, Leo and Schweigert, Florian J.},
  title     = {Plasma concentration of alpha-tocopherol in different free-ranging birds of prey},
  series = {European journal of wildlife research},
  volume    = {57},
  journal   = {European journal of wildlife research},
  number    = {5},
  publisher = {Springer},
  address   = {New York},
  issn      = {1612-4642},
  doi       = {10.1007/s10344-011-0516-z},
  pages     = {1043 -- 1049},
  year      = {2011},
  abstract  = {In this study, we investigated the alpha-tocopherol plasma concentrations in healthy free-ranging nestlings of the white-tailed sea eagle (Haliaeetus albicilla) (n=32), osprey (Pandion haliaetus) (n=39), northern goshawk (Accipiter gentilis) (n=25), common buzzard (Buteo buteo) (n=31), and honey buzzard (Pernis apivorus) (n=18) as well as of free-ranging adults of the white-tailed sea eagle (n=10), osprey (n=31), and northern goshawk (n=45). alpha-Tocopherol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. alpha-Tocopherol plasma concentrations in nestlings of osprey, white-tailed sea eagle, and northern goshawk did not differ significantly amongst the species, but the common buzzard and honey buzzard nestlings had significantly lower alpha-tocopherol plasma concentrations than nestlings of the other species (both P<0.001). Adult male ospreys and white-tailed sea eagles had significantly higher alpha-tocopherol concentrations compared to adult females (both P<0.005). Adult ospreys and northern goshawks had significantly higher alpha-tocopherol plasma concentrations compared to their nestlings (both P<0.001). In adult female northern goshawks, plasma concentrations of alpha-tocopherol increased significantly before egg laying (P<0.001). These results demonstrate alpha-tocopherol plasma concentrations in birds of prey to be species specific and influenced by age and reproductive status.},
  language  = {en}
}